I have a problem with my code in the try block.
To make it easy this is my code:
try:
code a
code b #if b fails, it should ignore, and go to c.
code c #if c fails, go to d
code d
except:
pass
Is something like this possible?
….
Defining a parameterless exception:
class MyException(Exception):
pass
When raised, is there any difference between:
raise MyException
and
raise MyException()
I couldn’t find any; is it simply an overloaded syntax?
….
I want to read a .csv file in python.
I don’t know if the file exists.
My current solution is below. It feels sloppy to me because the two separate exception tests are awkwardly juxtaposed.
Is there a prettier way to do it?
import csv
fName = “aFile.csv”
try:
with open(fName, ‘r’) as f:
reader = csv.reader(f)
for row in ….
In another question, the accepted answer suggested replacing a (very cheap) if statement in Python code with a try/except block to improve performance.
Coding style issues aside, and assuming that the exception is never triggered, how much difference does it make (performance-wise) to have an exception handler, versus not having one, versus having….
I want to save the name of the error and the traceback details into a variable. Here’s is my attempt.
import sys
try:
try:
print x
except Exception, ex:
raise NameError
except Exception, er:
print “0”, sys.exc_info()[0]
print “1”, sys.exc_info()[1]
print “2”, sys.exc_info()[2]
Output:
0
What is the best way to get exceptions’ messages from components of standard library in Python?
I noticed that in some cases you can get it via message field like this:
try:
pass
except Exception as ex:
print(ex.message)
but in some cases (for example, in case of socket errors) you have to do something like this:
try:
pass
except socket.err….
My background is in C# and I’ve just recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It’s quite easy in C#, but how do I do it in Python?
Eg. in C# I would do something like this:
try
{
ProcessFile(filePath);….
I know that if I want to re-raise an exception, I simple use raise without arguments in the respective except block. But given a nested expression like
try:
something()
except SomeError as e:
try:
plan_B()
except AlsoFailsError:
raise e # I’d like to raise the SomeError as if plan_B()
# didn’t raise th….
I have some a list comprehension in Python in which each iteration can throw an exception.
For instance, if I have:
eggs = (1,3,0,3,2)
[1/egg for egg in eggs]
I’ll get a ZeroDivisionError exception in the 3rd element.
How can I handle this exception and continue execution of the list comprehension?
The only way I can think of is to use a helpe….
A third-party library (written in C) that I use in my python code is issuing warnings. I want to be able to use the try except syntax to properly handle these warnings. Is there a way to do this?
….